18878140 has 48 divisors (see below), whose sum is σ = 41291712. Its totient is φ = 7243776.

The previous prime is 18878129. The next prime is 18878141. The reversal of 18878140 is 4187881.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a self number, because there is not a number n which added to its sum of digits gives 18878140.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18878141) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71649 + ... + 71911.

It is an arithmetic number, because the mean of its divisors is an integer number (860244).

Almost surely, 2^18878140 is an apocalyptic number.

18878140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18878140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20645856).

18878140 is an abundant number, since it is smaller than the sum of its proper divisors (22413572).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18878140 is a wasteful number, since it uses less digits than its factorization.

18878140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406 (or 404 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 37.

The square root of 18878140 is about 4344.8981576097. The cubic root of 18878140 is about 266.2684647057.

The spelling of 18878140 in words is "eighteen million, eight hundred seventy-eight thousand, one hundred forty".